The summer signing from Borussia Dortmund delivered another superb pre-season display for his new club, in turn raising questions over the logic behind a move for Arsenal's skipper

COMMENTBy Joe Doyle

Shinji Kagawa played a pivotal role in Manchester United's 4-3 win in a thrilling encounter against German side Hannover, scoring the winning goal for the Premier League side after a quite superb all-round display back in the country where he emerged as a potential superstar.

It rounded off an impressive pre-season for the only United signing so far this summer that is likely to affect the starting XI, with Nick Powell's arrival from Crewe one seemingly more for the future than an immediate return.

Kagawa's natural position - behind the striker - was where the winning goal came from, as he linked up well with Wayne Rooney (who recovered from a nightmare 45 minutes against Barcelona) to slot past Ron-Robert Zieler in the closing stages.

But questions remain as to what Sir Alex Ferguson's final formation for the season will be. Undoubtedly, it won't feature Michael Carrick at centre-back and Antonio Valencia as right-back like in Germany, but where Kagawa will feature most prominently is still unknown.

The ball falls to the unmarked Japanese playmaker on the right of the Hannover box after great link-up play with Wayne Rooney. Still with a lot to do, Kagawa then fires a bobbling effort past Ron-Robert Zieler and into the bottom corner from an awkward angle. Great finish.

Kagawa has already put in good performances for the club against Hannover and his subsitute role versus Barcelona, and while Van Persie is undoubtedly a quality player, the acquisition of the Japanese international, allied with United's already strong attacking line-up negates, in many ways, the need for the Dutch striker.

Van Persie is of course a striker any team would want among their ranks, but Rooney is United's point man up front.

Signing the Dutchman would not change this.

While it would give United an incredible alternative if the England striker suffered another notorious loss in form, Van Persie would again be relegated to a second striker role - something he didn't exactly prosper under at Arsenal.

It would be foolish to say that United should not sign Van Persie only for Kagawa's benefit. But if they are to play to all of their current players' strengths, the arrival of Kagawa would be seriously undermined by Van Persie's signature.

Van Persie joining could also signal a change of formation to 4-4-2, with Rooney alongside the Arsenal man up front. And with Antonio Valencia, Nani and Ashley Young all vying for the two spots on the wings, Kagawa would be unlikely to play wide.

A 4-2-3-1 with Kagawa taking Young's place could happen, but wouldn't particularly help the new recruit, who has struggled on the flanks for Dortmund.

A deeper role in midfield would not particularly suit the Japanese international, who scored 13 goals and made another eight in the Bundesliga last year, either. If United have flourished on the back of universal versatility from the likes of Park Ji-Sung and John O'Shea in recent years, Kagawa is a sea change.

Van Persie truly flourished in a lone-striker role, something he will not get at Old Trafford. While improved service from the wings could see him prosper, he would be up against much stronger competition from his new team-mates, with Danny Welbeck and Chicharito both aiming for a starting role, and Dimitar Berbatov's situation still unresolved, though Van Persie's arrival would surely herald the end for one of Old Trafford's silkiest ever strikers.

Arsenal's No.10 had a fantastic year as the main man in north London, and the Gunners looking toothless without him at some stages last year. But is signing him really necessary for United?

Kagawa will bring a balance to the side, something needed especially in Europe, where 4-4-2 is the formation of the past. United were badly exposed in the group stages of the Champions League last year, and the attack isn't the place they should be looking to strengthen this year.

This is set to be Paul Scholes' last year of football (again), and if Anderson doesn't finally come good this year, United will be short on quality in the central area of the pitch - something bigger sides will ruthlessly expose. Again.

A transfer for Van Persie could prove a master stroke. But Sir Alex should now be spending what funds he can squirm from the American owners on rejuvenating the places that really need it.

While he missed out on the capture of Lucas Moura thanks to the nouveau-riche Paris Saint-Germain, he should by no means abandon his quest for a central midfielder.

Kagawa is more than enough in the way of attacking supplements for this year, in what is already an impressive line-up for United. Would Van Persie improve the attack? Certainly. But with money tight and greater gaps elsewhere, the Dutchman would be a luxury, rather than a neccessity at Old Trafford. A luxury, you suspect, United can seldom afford.